Dispensing fitments have become commonplace in the packaging of many liquids and some solids. Commonly, some fitments may be attached to the sidewall of a container, which in some instances are made from paperboard. In these cases the fitment surrounds an orifice in the container wall and includes an upstanding spout to facilitate dispensing of the contents. The internal bore of the spout is initially closed by a membrane attached to the sidewall of the spout through a frangible line of weakness. On initial opening, a consumer grasps a “pull ring” attached to the membrane and pulls. This action results in removal of the membrane along the line of weakness and thereby clears a substantial portion of the bore for dispensing. It is noted that the initial intact membrane serves not only as a primary seal but also a tamper evidencing function. A quintessential example of such a “removable membrane” fitment is taught in U.S. Pat. No. 5,810,184 to Adams et. al.
Such removable membrane fitments have been marketed for many years. However, their market presence increased dramatically during the decade of 1990 due to their use on the classic “gable top” liquid packaging. This packaging development was enthusiastically received by the consuming public by improving product dispensing from an historically unwieldy package. More recently, similar removable membrane fitments have been employed with bottles. In these applications, the fitments are formed with structure designed to engage complimentary “fitment engaging structure” positioned on the exterior surface of the bottle neck. The removable membrane fitment offers widely recognized and accepted tamper evidencing function and potentially improves sealing and freshness in a way which is easily recognized and understood by the consumer. Embodiments of “removable membrane” fitments designed for use in conjunction with bottles are taught in U.S. patent application Ser. No. 10/854,925 to Lohrman et al.
Despite their success and consumer acceptance, some aspects of the removable membrane closures remain troublesome in both paperboard and bottle applications. One such aspect involves the use of an additional overcap that normally accompanies the fitment to provide a reseal capability once the membrane is removed. This overcap is of course a second piece to the closure system which must be assembled to the fitment prior to application of the assembly to the container. The overcap adds considerably to the cost of the closure.
An additional problem is that variations in manufacture occasionally result in the frangible removable membrane being tougher than desired, resulting in excessive removal forces associated with initial membrane removal. The pull ring integrity can also be dependent on the direction of pull. The combination of these conditions results in the possibility of the pull ring breaking away prematurely, leaving the frangible line intact with the entire membrane or a portion thereof still attached to the side wall of the spout.
An additional concern with conventional removable membrane fitment designs is that the internal bore involved is often in the range of about 20 mm to 38 mm. The membrane when removed results in a disk shaped piece of about 20 mm to 38 mm. This could present a choking hazard when handled by children. Fortunately, this has not been a practical concern, since most removable membrane closures have been used on larger packaging not independently consumed by unsupervised children.
In another segment of liquid packaging, developed for health or refreshment, a number of products are aimed at single serve portions, and more specifically single serve portions for children and young adults (hereinafter referred to as “youth” beverages). These packages historically have been in the form of aseptic boxes or bags such as the familiar “juice box”. The juice box suffers from its requirement of a straw for dispensing. The straw is an extra component that must be attached to the individual package. The straw has a sharpened end to facilitate initial puncture of the package. Once inserted, the package can be used as a “squirt gun” by squeezing. These latter aspects can result in troublesome situations in group child activities. Finally, because of the multi-material structures, including metals, employed with the juice box, recycling concerns have been advanced.
Another segment of packaging geared to youth beverages are packages intended to supply single service portions of nutritional liquids, primarily milk, in school lunch programs. These familiar packages are typically 8 ounce volumes made of paperboard materials. Since this product is refrigerated, there is no aseptic requirement. These packages suffer from being notoriously difficult to open for a child. The packages are difficult to manipulate, resulting in excessive spillage and mess.
Recently, single service packages suitable for youth beverages have appeared using an actual plastic bottle as the container (referred to as a “youth bottle”) rather than a boxes or bags. This packaging offers the promise of easier operation in the hands of minors. The packages are relatively rigid and have a well defined exit orifice for controlled dispensing. Aseptic packaging is not always a requirement. Thus, these plastic bottles are of a single material (typically polyethylene or polyethylene terephthalate (PET)) totally compatible with existing high volume recycling streams and methods. In these cases the bottle materials and manufacturing methods are limited in scope and reasonably well defined. However, the closure for these single service packages can vary considerably.
One possible choice of closure for the single service youth bottle is a standard snap-on or screw-on closure. In these packages, the packaging must be of minimal expense. However, this requirement cannot force a closure design which sacrifices seal integrity and tamper evidence in the interests of economy. Thus, standard closure designs can fail to meet the overall balance of requirements.
Another type of closure system for the single service youth bottle is a membrane which is sealed to the bottle top lip after filling with liquid. Such membranes may incorporate a metal foil for easier, more secure application and secure seal. These foils are relatively inexpensive compared to a conventional closure. However, they do present packaging line difficulties in application. In addition, the heat sealed membranes can be difficult to remove since there is little overhang to grasp. Removal is especially difficult for a child. The membranes often tear along a roughly diametrical line rather than peeling off the lip, and portions may remain on the bottle lip presenting a hazard.
Thus, there exists a need for improved closure systems for packaging of single service amounts of consumable liquids, especially those products which can be generally classified as “youth” beverages.